Question

How can my Chrysler LHS 2000 3.5L engine not pump oil after a replacement of valve cover gasket and timing belt?

My 2000 Chrysler LHS 3.5L car drove well over 12 hours (331 miles one way Greenwood SC to Bessemer AL) in one day without any problem. After a timing belt & valve cover gasket replacement, can my mechanics miss out installing something like a connector (maybe oil pressure sending unit or sensor) that cause my car engine oil no longer pumped and thus engine overheated. Now my mechanics told because my car oil pump just quit which does not make any sense.

I suspect he did not put back the oil pressure sending unit connector behind the back of the plenum. Can you tell me where this connector is?

I checked the oil when picking the car up, and there is no sign that the oil is pumped up because there is no sign of any oil on the top of the oil dipstick at all after the engine started, and a wait for 2 minutes for the oil to settle down. Usually after the oil change, I started the engine and run for 2 minutes, stopped the engine, and check the oil dipstick. There always some oil on the top of the dipstick because the oil is splashed around and dropped back down.

If your oil pump wasn't working, the car wouldn't overheat, but rather the engine would seize in a red hot minute. Sounds like you are on the wrong track here for diagnosing your problem. An engine cannot run very long without an oil pump and it will make an unholy racket as soon as you start it up.

I just finished my son in laws 99 chrysler 300m with 3.5 engine. May be the same problem your having. "No oil pressure to top of engine -lash adjusters clattering - and oil lite coming on while driving."

The dealer offered to do a hot flush, then claimed the engine and car not worth the work. They should have known the issues with this engine and relayed that back to the customer. I dropped the oil pan and found sludge in the oil pan, oil pan tray, and a thick coating in the oil pickup screen. Main bearings were barely worn, but the rod bearings were badly worn into the copper backing. All this started as a "sudden" problem with no indication of impending failure.

The PCV valve is under sized as the engine produces less blowby (when new) than most engines. When worn, the PCV valve cannot handle the blowby volume and sludging occurs. The oil pick up in the bottom of the oil pan is likely plugged with sludge, restricting oil flow. Along with this, the crank throws are offset (potential oil flow problems when dirty, sludgy or low oil press) and the rod bearings are likely worn.

Ask your shop guy how much crusty oil sludge was present under the valve cover and figure about the same or more in the oil pan. Your engine was disturbed and you have either flushed or loosened sludge particles into the oil pickup.

Cost of the repair parts came in about 150$. Add 1500$ - 2500$ if you have to pay for labour.

In other research there is (was) a class action lawsuit over sludging issues.